Not All that Glitters is Gold
Precious metals are rare elements that have high economic value. Perhaps best known for their use in jewellery, they are also used in industrial processes, or very often as investment vehicles. The primary precious metals are gold, silver, and palladium which may be alloyed with a variety of elements, depending on the application, to improve the properties of the final product.
Fine gold is basically pure gold with fineness of 999 or above. Gold alloys include yellow gold, which has silver as the main alloying element, rose gold, which is alloyed with copper, and white gold, which has either palladium or nickel as the main alloying elements.
Determining what other precious metals besides gold may be present in a sample can be a challenge. It may also be difficult to determine the right karats or to detect gold plating. An important issue is the difficulty of keeping the sample intact when doing a test to determine the true precious metal content of a sample. Another challenge is the market competition. Pawn shops and cash for gold businesses have to offer very high prices to close a deal, and at the same time, make sure that the transaction is profitable. Margins are very tight, and the price of gold fluctuates every day. But one of the biggest risks is people trying to commit fraud.
Verification tests that business use to combat these risks include the scratch and acid test, which is widely used but not very accurate and potentially dangerous. The most precise method is fire assay, but this method destroys the sample. Laboratory methods with expensive machines require extensive sample preparation. Finally, there is portable X-ray florescence (XRF), a non-destructive method that measures up to 22 elements in one reading. For businesses that need an accurate, fast, easy, non-destructive method for a reasonable price, portable XRF analysers are the best possible solution among all the techniques.